The present invention relates to a method for transmitting messages that are specific to xe2x80x9cMWI Servicexe2x80x9d in telecommunication Networks, particularly in hybrid DECT/ISDN-Specific Telecommunication Networks.
In message systems having a message transmission path between a message source and a message sink, transmitting and receiving devices are used for processing and transmitting messages, in which devices
1) the message processing and transmission can be accomplished in a preferred direction of transmission (simplex mode) or in both directions (duplex mode),
2) the message processing is analog or digital,
3) messages are transmitted over the telecommunication path wirelessly on the basis of diverse message transmission methods FDMA (Frequency Division Multiple Access), TDMA (Time Division Multiple Access) and/or CDMA (code Division Multiple Access), for instance in accordance with radio standards such as DECT, GSM, WACS, or PACS, IS-54, IS-95, PHS, PDC, etc., (cf. IEEE Communications Magazine, January 1995, pp. 50-57; DD Falconer et al: xe2x80x9cTime Division Multiple ACCESS Methods for Wireless Personal Communicationsxe2x80x9d), and/or are transmitted over wire.
xe2x80x9cMessagexe2x80x9d is an overarching term referring both to the meaningful content (information) and the physical representation (signal). Despite the same content of a messagexe2x80x94i.e. the same informationxe2x80x94different signal forms can occur. Thus, a message relating to a subject matter can be transmitted
(1) in the form of an image,
(2) as a spoken word,
(3) as a written word,
(4) as an encrypted word or image.
The type of transmission in accordance with images, spoken words, and written words is normally characterized by continuous (analog) signals, while in the type of transmission in accordance with encrypted words or image discontinuous signals (e.g. impulses, digital signals) usually occur.
Based on this general definition of a message system, the present invention relates to a method for transmitting messages which are specific to xe2x80x9cMWI servicexe2x80x9d in telecommunication networks, particularly in hybrid DECT/ISDN-specific telecommunication networks.
Hybrid telecommunication networks include network containing various wireless and/or wirebound telecommunication subnetworks or subsystems.
Telecommunication systems of the above described type include DECT systems [Digital Enhanced (previously: European) Cordless Telecommunication; cf. (1): Nachrichten Elektronik 42 (1992) Jan/Feb, Nr. 1, Berlin, Del.; U. Pilger xe2x80x9cStruktur des DECT Standardsxe2x80x9d, pp. 23-39 together with ETSI Publication ETS 300175-1 . . . 9, October 1992; (2): Telcom Report 16 (1993), Nr. 1, J. H. Koch: xe2x80x9cDigitaler Komfort fxc3xcr schnurlose Telekommunikationxe2x80x94DECT Standard eroffnete neue Nutzungsgebietexe2x80x9d, pp. 26 and 27; (3): tec 2/93xe2x80x94The technical magazine by Ascom xe2x80x9cWege zur universellen mobilen Telekommunikationxe2x80x9d, pp. 35-42; (4) Philips Telecommunication Review, Vol.49, No. 3, September 1991, R. J. Mulder: xe2x80x9cDECT, a Universal Cordless Access Systemxe2x80x9d; (5): WO 93/21719 (FIGS. 1 to 3 with description)] or GAP systems (Generic Access Profile; cf. ETSI Publication ETS 300444, December 1995, ETSI, FR), which can be constructed according to the representation in FIG. 1, for example. The GAP standard is a subset of the DECT standard, whose object is to ensure the interoperability of the DECT air interfaces for telephone applications.
In accordance with the DECT/GAP standard, according to the representation in FIG. 1, at a DECT/GAP base station BS of a DECT/GAP system DGS a maximum of 12 connections can be set up, in accordance with the DECT/FDMA/TDD method, parallel to DECT/GAP mobile parts MT1 . . . MT12 via a DECT/GAP air interface that is laid out for the frequency range between 1.88 and 1.90 GHz. The number 12 derives from a number xe2x80x9ckxe2x80x9d of time slots or telephone channels, that are available for the duplex mode of the DECT GAP system DGS (k=12). The connections can be internal or external. Given an internal connection, two mobile parts, for instance mobile parts MT2 and MT3, that are registered at the base station BS can communicate with one another. For the construction of an external connection, the base station BS is connected to a telecommunication network TKN, for instance in a wirebound manner via a telecommunication terminal unit TAE, or a private branch exchange NStA is connected to a cablebound telecommunication network or in accordance with PCT Patent Application No. 95/05040 to a higher-ranking telecommunication network wirelessly as a repeater station. Given external connection, using a mobile part, for instance mobile part MT1, it is possible to comnmunicate with a subscriber in the telecommunication network TKN via the base station BS and the telecommunication terminal unit TAE or private branch exchange NStA. If the base station BS has only one connection to the telecommunication terminal unit TAE or to the private branch exchange NStA, as in the case of the gigaset 951 (Siemens cordless telephone, see telecom report 16 (1993), vol. 1, pp. 26 and 27), then only one external connection can be set up. If the base station BS has two connections to the telecommunication network TKN,xe2x80x94as in the case of the gigaset 952 (Siemens cordless telephone, see telecom report 16, (1993), vol. 1, pp.26-27), then, besides the external connection to the mobile part MT1, an additional external connection is possible from a wirebound communication terminal device TKE that is connected to the base station BS. In principle, it is also imaginable that a second mobile part, for instance mobile part MT2, would use the second connection for an external connection, instead of the communication terminal device TKE. Whereas the mobile parts MT1 . . . MT2 are driven by a battery or an accumulator, the base station BS, which is implemented as a cordless advanced network processor system, is connected to a voltage network SPN via a network terminal device NAG.
FIG. 2 shows the principal circuit construction of the base station BS and the mobile part MT on the basis of the reference Components 31 (1993), Vol. 6, pp. 215 to 218; S. Althammer, D. Brxc3xcckmann. xe2x80x9cHochoptimierte ICs fxc3xcr DECT Schnurlostelefonexe2x80x9d. The base station BS and the mobile part MT comprise a radio part FKT having an antenna ANT, which is allocated to transmission and reception of radio signals, as well as a signal processor SVE and a central control ZST, which are connected to one another in the manner depicted. The radio part FKT essentially contains the known systems such as transmitter SE, receiver EM and synthesizer SYN. The signal processing system SVE contains a coder/decoder CODEC, among other systems. The central control ZST comprises a microprocessor xcexcP for both the base station BS and the mobile part MT, which has a program module that is constructed in accordance with the OSI/ISO layer model [see. (1): Instructional publicationsxe2x80x94Deutsche telecom, Issue 48, 2/1995, pp. 102 to 111; (2): ETSI Publication ETS 300175-1 . . . 9, October 1992], a signal control part SST, and a digital signal processor DSP, which are connected to one another as illustrated. Of the layers that are defined in the layer model, only the first four layers are shown, which are of immediate and critical importance to the base station BS and the mobile part MT. The signal control part SST is realized in the base station BS as a time switch controller TSC and in the mobile part MT as a burst mode controller BMC. The critical difference between the two signal control parts TSC, BMC is that the signal control part TSC that is specific to the base station BS assumes additional switching functions beyond those performed by the signal control part MT BMC that is specific to the mobile part.
The principal mode of operation of the above described circuit units is described in the above cited reference Components 31 (1993), vol. 6, pp 215-218.
The described circuit construction according to FIG. 2 is expanded in the base station BS and the mobile part MT by additional functional units according to their function in the DECT/GAP system according to FIG. 1.
The base station BS is connected to the telecommunication network TKN via the signal processing system SVE and the telecommunication terminal unit TAE, or the private branch exchange NStA, and it additionally comprises an answering machine AB. As an option, the base station BS can also have an operator interface (hatched units in FIG. 2), consisting, for example, of an input means EE implemented as a keyboard, a display means AE implemented as a screen, a speaking/listening device SHE implemented as a handset having a microphone SHE and a receiver inset HK, and a tone ringing bell TRK.
The mobile part MT comprises the user interface that is a possible option of the base station BS, which has the above described operating elements that pertain to this user interface.
FIG. 3 shows the TDMA structure of the DECT/GAP system DGS (see xe2x80x9cNachrichtentechnik Elektronik 42 (1992) Jan/Feb, Nr. 1, Berlin, Del.; U. Pilger: xe2x80x9cStruktur des DECT Standardsxe2x80x9d, pp 23-29 with ETS 300 175-1 . . . 9, October 1992xe2x80x9d). The DECT/GAP system is a hybrid system in terms of the multiplex method, wherein radio messages can be transmitted from the base station BS to the mobile part MT and from the mobile part MT to the base station BS (Time Division Duplex mode) in accordance with the FDMA principle on ten frequencies in the frequency band between 1.88 and 1.9 Ghz in accordance with the TDMA principle according to FIG. 2 in a predetermined time sequence. The time sequence is determined by a multi-time-frame MZR, which occurs every 160 ms and which has 16 time frames ZR with a duration of 10 ms each. In these time frames ZR, information relating to a C, M, N, P, Q channel that is defined in DECT is transmitted to the base station BS and the mobile part MT separately. When information for several of these channels is transmitted in one time frame ZR, the transmission follows a priority list with M greater than C greater than N and P greater than N. Each of the 16 time frames ZR of the multi-time-frame MZR is subdivided into 24 time slots ZS, in turn, each having a duration of 417 Ps, 12 of which (time slots 0 . . . 11) are specified for the transmission direction xe2x80x9cbase station BSxe2x86x92mobile part MTxe2x80x9d, and the other 12 of which (time slots 12 . . . 23) are specified for the direction xe2x80x9cmobile part MTxe2x86x92base station BS.xe2x80x9d In each of these time slots ZS, information having a bit length of 480 bits is transmitted in accordance with the DECT standard. Of these 480 bits, 32 bits are transmitted as synchronization information in a SYNC field, and 388 bits are transmitted as message information in a D field. The remaining 60 bits are transmitted as additional information in a Z field and as security information in a field xe2x80x9cguard timexe2x80x9d. The 388 bits of the D field which are transmitted as payload information are subdivided in turn into a 64-bit A field, a 320-bit B field, and a 4-bit xe2x80x9cX-CRCxe2x80x9d word. The 64-bit A field is composed of an 8-bit data header, a 40-bit data record with data for the C, Q, M, N, P channels, and a 16-bit xe2x80x9cA-CRC wordxe2x80x9d.
On the basis of the DECT/GAP system DGS according to FIG. 1, FIG. 4 shows a cellular DECT/GAP multisystem CMI (Cordless Multicell Integration), in which several of the above described DECT/GAP systems DGS are present, each having a base station BS and one/several mobile part(s) MT at an arbitrary geographic location; for instance, concentrated in an administration building having open-plan offices on several floors in an office building (in the sense of a hot spot arrangement). However, instead of a xe2x80x9cclosedxe2x80x9d geographic location such as an office building, an xe2x80x9copenxe2x80x9d geographical location with strategic telecommunication importancexe2x80x94such as city squares having a high volume of traffic, a high concentration of businesses and a large flow of peoplexe2x80x94is also possible for the installation of a cellular DECT/GAP multi-system CMI. Part of the base stations BS that are arranged in the open-area office are realized as antenna diversity base stations in accordance with PCT patent application Ser. No. 94/10764, in contrast to the base stations illustrated in FIGS. 1 and 2. The concentration of the DECT/GAP systems DGS is expressed (contiguous radio coverage of the geographic location) such that individual DECT/GAP systems DGS operate in the same environment by virtue of the overlapping DECT/GAP radio coverage areas FB.
Depending on the degree of overlap, identical environment can mean that: a) a first base station BS1 of a first DECT/GAP system DGSI is arranged in a first radio coverage area FB1, and a second base station BS2 of a second DECT/GAP system DGS2 is arranged in a second radio coverage area FB2, which systems can set up telecommunication connections to at least one mobile part MT1,2, b) a third base station BS3 of a third DECT/GAP system DSG3 and a fourth base station BS4 of a fourth DECT/GAP system DGS4 are arranged in a common third radio coverage area FB3 and can set up telecommunication connections to at least one mobile part MT3,4.
The cordless telecommunication scenario illustrated in FIGS. 1 to 4, in which DECT mobile parts can be connected to a private (residential) DECT base station (FIG. 1 ) or to one or more private or public DECT base stations (FIG. 4), via a DECT air interface can now be expanded in accordance with the publication xe2x80x9cLecture by A. Elberse, M. Barry, G. Fleming. xe2x80x9cDECT Data Servicesxe2x80x94DECT in Fixed and Mobile Networksxe2x80x9d, Jun. 17./18. 1996, Hotel Sofitel, Paris;pp 1-12 and abstractxe2x80x9d such that the DECT mobile parts are connectible to private and public DECT base stations via the DECT air interface.
According to PCT Patent Application No. 95/5040 (see FIGS. 3 through 8 therein with the respectively pertaining description), this scenario can then in turn be expanded in view of a universal mobile telecommunication system (UMTS) to the effect that pico-cell-related cordless telecommunication systems (for example, the previously discussed DECT systems from CTM points of view (cordless terminal mobility; CETSI Publications (1): xe2x80x9cIN Architecture and Functionality for the support of CTMxe2x80x9d, Draft Version 1.10, September 1995; (2): xe2x80x9cCordless Terminal Mobility (CTM)xe2x80x94Phase 1, Service Descriptionxe2x80x9d, draft DE/NA-010039, Version 6, Oct. 2, 1995) be linked into a higher-ranking network INFRA structure (for example, ISDN, PTSN, GSM and/or satellite networks) for accesses (see ETSI Publication, xe2x80x9cCTM Access Profile (CAP)xe2x80x9d, prETS 300824, November 1996). According to patent claim 1 of PCT Patent Application No. 95/05040, this can be achieved by a DECT base station fashioned as DECT repeater. In a universal mobile telecommunication system, DECT is mainly understood as a xe2x80x9cnetwork access technologyxe2x80x9d for mobile communication services (see the presentation of A. Elberse, M. Barry, G. Fleming on the subject, xe2x80x9cDECT Data Servicesxe2x80x94DECT in Fixed and Mobile Networksxe2x80x9d, Jun. 17/18, 1996, Hotel Sofitel, Paris; Pages 1 through 12 and summary) and not as a network.
Standing for the scenario presented above, FIG. 5xe2x80x94proceeding from the publications xe2x80x9cNachrichtentechnik Elektronikxe2x80x9d, Berlin 45, (1995), No.1, Page 21 through 23 and No. 3, Pages 29 and 30, as well as IEE Colloqium 1993, 173; (1993), pages 29/1-29/7, W. Hing, F. Halsall: xe2x80x9cCordless access to the ISDN basic rate servicexe2x80x9d on the basis of a DECT/ISDN intermediate system DIIS according to ETSI Publication prETSxe2x80x94300822, February 1997xe2x80x94shows an ISDN⇄DECT Telecommunication system ID-TSZ (Integrated Services Digital Network⇄Digital Enhanced Cordless Telecommunication) with an ISDN telecommunication sub-system I-TKN [see the publication xe2x80x9cNachrichtentechnik Elektronikxe2x80x9d, Berlin 41-43, Parts 1 through 10, Part 1: (1991) No. 3, pages 99 through 102; Part 2: (1991) No. 4, pages 138 through 143; Part 3: (1991) No. 5, Pages 179 through 182 and No. 6, pages 219 through 220; Part 4: (1991) No. 6, pages 220 through 222 and (1992) No. 1, pages 19 through 20; Part 5: (1992) No. 2, pages 59 through 62 and (1992) No. 3, pages 99 through 102; Part 6: (1992) No. 4, pages 150 through 153; Part 7: (1992) No. 6, pages 238 through 241; Part 8: (1993) No. 1, pages 29 through 33; Part 9: (1993) No. 2, pages 95 through 97 and (1993) No. 3, pages 129 through 135; Part 10: (1993) No. 4, pages 187 through 190] and a DECT telecommunication sub-system D-TTS.
As shall be explained in greater detail below, the DECT telecommunication system D-TKS can thereby be a component part of a DECT/ISDN intermediate system DIIS or of a RLL/WLL telecommunication sub-system RW-TTS. The DECT telecommunication system D-TKS and, thus, the DECT/ISDN intermediate system DIIS or the RLL/WLL telecommunication sub-system RW-TTS are preferably based on a DECT/GAP system GDS as shown, for example, in FIG. 1.
Alternatively, the DECT/ISDN intermediate system DIIS or the RLL/WLL telecommunication sub-system RW-TTS can also be based on a GSM system (global system for mobile communication; see Informatik Spektrum 14 (1991) June, No. 3, Berlin, Del.; A. Mann: xe2x80x9cDer GSM-Standardxe2x80x94Grundlage fxc3xcr digitale europxc3xa4ische Mobilfunknetzexe2x80x9d, pages 137 through 152). Instead, it is also possible within the scope of a UMTS scenario that the ISDN telecommunication system I-TKN is fashioned as GSM system or as PSTN system (public switched telecommunications network).
Coming into consideration over and above this as further possibilities for the realization of the DECT/ISDN intermediate system DIIS or of the RLL/WLL telecommunication sub-system RW-TTS or of the ISDN telecommunication sub-system RW-TTS are the initially cited systems as well as future systems that are based on known multiple access methods FDMA, TDMA, CDMA (Frequency Division Multiple Access, Time Division Multiple Access, Code Division Multiple Access) and hybrid multiple access methods formed therefrom.
The employment of radio channels (for example DECT channels) in classic line-bound telecommunication systems such as the ISDN (RLL/WLL scenario) is gaining increasingly in significance, particularly as viewed against the background of future, alternative network operators without their own complete wire network.
Given, for example, the RLL/WLL telecommunication sub-system RW-TTS, thus, the wireless connection technique RLL/WLL (radio in the local loop/wireless in the local loop) shall make ISDN services available to the ISDN subscriber at standard ISDN interfaces, for example upon involvement of the DECT system DS (see FIG. 4).
In the ISDN⇄DECT telecommunication system ID-TS according to FIG. 5, a first telecommunication subscriber (user) TCU1 (telecommunication user) has his terminal equipment TE (terminal endpoint; terminal equipment) linked into the ISDN world with the services available therein, for example, via a standardized S-interface (S-bus), the DECT/ISDN intermediate system DIIS fashioned as local message transmission loopxe2x80x94preferably DECT-specific and contained in the RLL/WLL telecommunication sub-system RW-TTSxe2x80x94a network termination NT, and a standardized U-interface of the ISDN telecommunication sub-system I-TTS and, second, a second telecommunication subscriber TCU2 is also linked into said ISDN world with the services available therein as ultimate user of the DECT/ISDN intermediate system DIIS.
The DECT/ISDN intermediate system DIIS is essentially composed of two telecommunication interfaces, of a first telecommunication interface DIFS (DECT intermediate fixed system) and of a second telecommunication interface DIPS (DECT intermediate portable system) that are wirelessly connected to one another, for example via a DECT air interface. Due to the quasi-location-bound, first telecommunication interface DIFS, the DECT/ISDN intermediate system DIIS forms the local message transmission loop defined above in this context. The first telecommunication interface DIIS contains a radio fixed part RFP, an interworking unit IWU1 and an interface circuit INC1 to the S-interface. The second telecommunication interface DIPS contains a radio portable RPP and an interworking unit IWU2 and, potentially, an interface circuit INC2 to the S-interface. The radio fixed part RFP and the radio portable RPP thereby form the known DECT/GAP system DGS.
As already mentioned, FIG. 5 shows, first, (first possibility), how the DECT/ISDN intermediate system DIIS is linked into the ISDN telecommunication system I-TKN as local message transmission loop within the framework of the RLL/WLL telecommunication sub-system RW-TTS as typical RLL/WLL scenario and, second (second possibility), how the DECT/ISDN intermediate system DIIS is only connected to the ISDN telecommunication system I-TKN at the network side as seen from CAP points of view (cordless terminal ability access profiles). Given the second possibility, the interface circuit INC2 of the second telecommunication interface DIPS to the S-interface is not active or is not present at all. In order to graphically present and support this situation overall, the interface circuit INC2 of the second telecommunication interface DIPS is shown with broken lines. Whereas the second telecommunication interface DIPS given the first possibility, for example, is not fashioned mobile part-specific, i.e. with user interface, the second telecommunication interface DIPS in the second possibility is fashioned as typical mobile part with a user interface.
In the scope of the CTM Access Profile (CAP), which is standardized by ETSI, it is intended to realize the call-independent service xe2x80x9cMessage Waiting Indicationxe2x80x9d (MWI) (cf. ETSI Publication xe2x80x9cCTMACCESS Profile (CAP)xe2x80x9d prETS300???, September 1996, chapt. 4. Introduction).
MWI service informs the user of a cordless mobile part (for instance, a DECT mobilepart) that a message for the user is present in the network. This message can indicate that a third party has tried to call the user (e.g. indication of the status of voice mailbox) or that the third party has left the user a short message.
In accordance with the publications [(1) ETSI publication De.NA-010 033 xe2x80x9cISDN, Message Waiting Indication (MWI) Supplementary Service, Service Descriptionxe2x80x9d, Stage 1, Standard for MWI in Fixed (Public) ISDN, Draft version 5, October 1995); (2): ETSI Publication DE/SPS-05069-1: xe2x80x9cISDN, Message Waiting Indication (MWI) Supplementary Service, Digital Subscriber Signaling System No. 1(DSS1) Protocol, Part 1: Protocol Specificationxe2x80x9d, stage 3, Standard for MWI in Fixed (Public) ISDN, Version 5 rev. 1, September 1995); (3): ECMA Publication xe2x80x9cPrivate Telecommunication Networks (PTN), Specification, Functional Model and Information flows, Message Waiting Indication Supplementary Servicexe2x80x9d, Stage 1, Second Standard for MWI and PTN""s, Interim Fifth Draft, September 1995], various mandatory or optional MWI-specific procedures for providing MWI service are defined.
The mandatory procedures include;
1. a REGISTER procedure, with which a user of the MWI service provided in a network is registered by the network company manually, and
2. an INDICATE procedure, with which the message type and the number of messages for the user of the MWI service are indicated to him.
The optional procedures include the ACTIVATE or DEACTIVATE procedures or an INTERROGATE procedure, which are not discussed further in the context of the present invention.
Of the mandatory procedures, only the INDICATE procedure is examined and described more comprehensively here. The relevant comments can basically be applied to the other procedures that are mentioned above in an equivalent manner. Beyond this, with the procedures cited above for providing MWI service, service-specific parameters are transmitted, which like the procedures, are either mandatory or optional. The mandatory parameters include;
1) the type of message for the user,
2) the number of messages for the user that are of the type defined according to 1.
The optional parameters include a message identifier assigned by the network, a CLIP number with which the calling person can be identified, and a date and time stamp of the received or deleted messages.
The MWI service is communicated and made available to the user of the DECT mobile part via a user-specific xe2x80x9cuser interfacexe2x80x9d (man machine interface); for instance, by tone signaling, displaying the MWI text, providing MWI-specific menu displays, and so on.
A variety of suggestions for realizing an MWI service have already been introduced and discussed publicly.
For example, one concept is to realize the MWI service, which is not mentioned explicitly in either the GSM standard or in the DECT/GSM standard, implicitly by transmitting a short message as provided in the GSM standard and in the DECT/GSM standard (ETSI Publication preETS 300764, April 1995;) (cf. Presentation by CSELT, ITALTEL and TELECOM ITALIA at the xe2x80x9cETSI-RES-03 Nxe2x80x9d meeting of May 20-22, 1996 in Madrid, 2 pages). Here, the DECT-specific information element xe2x80x9cIWU-TO-IWUxe2x80x9d (ETSI publication ETS 300175-5, October 1992, 7.7.23 and Annex G.3) are supposed to be used by a DECT base station (Fixed Part FP) that is connected to the DECT mobile part (Portable Part PP) by a DECT air interface for the transmission of the MWI service. In this proposal, the DECT mobile part for providing the MWI service must store the short messages with a length of e.g. 160 information units. The storage of short messages, as is common in GSM handhelds, is undesirable for the present DECT mobile parts due to the increase in the price of the mobile part that is associated with this storage process.
A further proposal for realizing the MWI service is concerned with how to implement the MWI service for DECT/ISDN systems. Proceeding from the publications (1): ETSI Publication De/NA-010 033 xe2x80x9cISDN, Message Waiting Indication (MWI) Supplementary Service, Service Description,xe2x80x9d Stage 1, Standard for MWI in Fixed (Public) ISDN, Draft Version 5, October 1995); (2): ETSI Publication DE/SPS-05069-1: xe2x80x9cISDN, Message Waiting Indication (MWI) Supplementary Service, Digital Subscriber Signalling System no. 1 (DSSI) Protocol, Part 1: Protocol Specificationxe2x80x9d, Stage 3, Standard for MWI in Fixed (Public) ISDN, Version 5, rev. 1, September 1995); and (3) ECMA Publication xe2x80x9cPrivate Telecommunication Networks (PTN), Specification, Functional Model and Information flows, Message Waiting Indication Supplementary Servicexe2x80x9d, Stage 1, Second Standard for MWI and PTN""s, Interim Fifth Draft, September 1995 and ETSI Publication ETS 300 175-5, October 1992, chapter 7.7.15, the underlying idea of this proposal is the transparent transmission, via the DECT air interface, of ISDN-specific services (such as the MWI Service) on the DECT side with the DECT protocol-specific information element xe2x80x9cFACILITYxe2x80x9d. This proposal contains a singular DECT/ISDN-specific solution which is suitable for realizing the MWI service for the CAP standard underlying the universal mobile telecommunication system.
A further alternative involves realizing the MWI service via a proprietary protocol, the DECT-specific information element xe2x80x9cESCAPE TO PROPRIETARYxe2x80x9d being used in this proprietary protocol (cf. ETSI Publicatoin 300 175-5, March 1996, chap. 7.7.45). This proprietary solution is likewise unsuitable for the CAP standard.
FIG. 6 shows one possible arrangement (configuration) for an MWI transmission (MWI scenario) based on the above embodiments. The configuration is a hybrid, for instance ISDN/DECT-specific telecommunication scenario ID-TSZ with a telecommunication network TKN that is fashioned as an ISDN network and a telecommucniatoin system DGS that is fashioned as a DECT/GAP system. The telecommunication system contains at least one DECT base station BS, RFP and at least one DECT mobile part MT, RPP that can be connected to the base station by wireless telecommunication. The mobile part MT, RPP and the base station BS, RFP are set up in accordance with the representation in FIG. 2. Individual functional units in the base station that are individual for explicating the MWI transmission are represented again. These functional units include the DECT radio part FKT, the central control ZST with microprocessor xcexcP for selection code interpretation, and the answering machine AB, which is the designated storage entity in the MWI context. Since the depicted configuration contains an additional storage entity, for instance what is known as the T-NET-BOX, which is arranged outside the telecommunication system DGS in the telecommunication network TKN, the storage entity that is realized as answering machine AB is designated INTERNAL storage entity or first storage entity SPI1, and the storage entity that is realized as T-NET-BOX is designated EXTERNAL storage entity or second storage entity SPI2. Besides the answering machine AB, what is known as a missed calls list may also come into consideration as INTERNAL storage entity.
With the configuration illustrated in FIG. 6. events (e.g. the storage of messages of a variety of types, which are to be transmitted from an arbitrary network subscriber to the users/proprietors of the DECT mobile parts MT, RPP) can be transmitted to the DECT mobile parts MT, RPP by means of the standardized procedure xe2x80x9cmessage waiting indicationxe2x80x9d.
These events are signaled to the user/proprietor of the mobile part in a suitable manner, for instance by an LED or a screen display.
A fundamental problem is that these events can occur both within and without the telecommunication system DGS (operative word: INTERNAL storage entity or EXTERNAL storage entity).
Regardless, it is a precondition that the user have a DECT mobile part that supports the MWI service, this service is used to indicate to the user at his terminal device that a message has arrived for him at the INTERNAL storage entity and/or at the EXTERNAL storage entity while he was not at home.
Upon returning home, the user sees the indication that has come in and calls the corresponding storage entity.
This is the source of another problem. Namely, the user does not know which storage entity to call, the INTERNAL or the EXTERNAL entity.
This is because of the fact that, although the DECT base station BS, RFP can differentiate external and internal events, it does not have the ability to signal this to the DECT mobile part MT, RPP allocated to it.
The object on which the present invention is based consists in being able to distinguish between internal and external messages in the transmission of messages that are specific to xe2x80x9cMWI servicexe2x80x9d in telecommunication networks, particularly in hybrid DECT/ISDN-specific telecommunication networks, for the purpose of displaying messages for the telecommunication subscriber that are filed in the telecommunication systems.
This object is inventively achieved in accordance with the present invention in a method for transmitting messages that are specific to xe2x80x9cMWI Servicexe2x80x9d in telecommunication networks, particularly in hybrid DECT/ISDN-specific networks, said method comprising the steps of:
transmitting a xe2x80x9cMWI-servicexe2x80x9d-specific message in a telecommunication system of a telecommunication network from a first telecommunication device to a second telecommunication device being specific to a telecommunication subscriber and being connected to said first telecommunication device by telecommunication;
indicating in said xe2x80x9cMWI-servicexe2x80x9d-specific message that messages have been stored for said telecommunication subscriber;
transmitting originator information from said first telecommunication device to said second telecommunication device, said originator information for identifying entities in said telecommunication network for storing said message;
transmitting additional information from said first telecommunication device to said second telecommunication device, said additional information indicating whether said message is stored in an internal entity or an external entity of said telecommunication system;
transmitting said originator information and said additional information from said second telecommunication device back to said first telecommunication device in a deferred manner; and
said first telecommunication device allocating said second telecommunication device to one of said internal entity and said external entity of said telecommunication system according to said transmitted back additional information.
The idea underlying the invention is that the equipment (e.g. the base station) that sends or forwards the MWI message to the terminal device (e.g. the DECT mobile part) that is allocated and connected to it transmits an additional indication that distinguishes between internal and external events.
This can have a variety of embodiments, though all of them can be traced back to the above stated fundamental solution.
According to the standardized protocol of the service xe2x80x9cMessage Waiting Indicationxe2x80x9d, said equipment can cosend the call number of the corresponding server in the message waiting indication signaling. Here, based on the configuration in FIGS. 6 to 12, the internal and external entities can be distinguished implicitly or explicitly with the aid of the call number.
Assume that the EXTERNAL storage entity has the number xe2x80x9c01301111xe2x80x9d, and that there is a message for the user of the mobile part. The EXTERNAL entity subsequently sends an ISDN message xe2x80x9cmessage waiting indicationxe2x80x9d (external message) to the base station, which forwards this message to the mobile part transparently via the DECT air interface. When the user wants to retrieve the message, he dials the cotransmitted number of the EXTERNAL entity. This number is transparently forwarded by the base station, in turn. When the base station has an internal message in the INTERNAL entity allocated to it, which is arranged in the base station or outside the base station but within the telecommunication system, then, as in the case of the external message, the base station sends a message that appears to the mobile part to be identical, with the difference that here the number is unambiguously distinct from an external number in accordance with the international and national number schema; for instance, one such unambiguous number would be xe2x80x9c***#*10100xe2x80x9d. When the user wants to retrieve the message, he dials this transmitted number of the INTERNAL entity. The base station evaluates the number dialed by the mobile part and branches to the internal entity if necessary.
The difficulty of this solution lies in specifying a suitable unambiguous number which does not conflict with national number schemas worldwide.
The indicated ISDN message xe2x80x9cMessage Waiting Indicationxe2x80x9d has additional information elements with the aid of which external events can be distinguished from internal events. These could be used by the mobile part either to address the base station internally or to address the telecommunication network externally. The problem in this solution is that the response of the allocated mobile part would vary depending on which information elements are sent by which network base stations. As a result, flexibility is lost in the mobile part, and even today it is necessary to adjust to a wide variety of network types.